Electrical conductivity copper oxide

Other electrically conductive transparent oxides include fluorine- and chlorine-doped oxides such as hn oxide (Sn02 FI) antimony-doped hn oxide (Sn02 Sb) cadmium oxide (CdO), Cd2Sn04 and aluminum-doped zinc oxide (ZnO A1 or ZAO). Non-transparent electrically conduchve oxides include chromium oxide (Cr203) the copper oxides (CuO, CU2O) lead oxide (PbO) and rubidium oxide (RbO). In addihon to sputter deposition, conduchve oxide films can also be prepared by spray pyrolysis, reachve evaporation, and CVD. 

For many electronic and electrical appHcations, electrically conductive resias are required. Most polymeric resias exhibit high levels of electrical resistivity. Conductivity can be improved, however, by the judicious use of fillers eg, in epoxy, silver (in either flake or powdered form) is used as a filler. Sometimes other fillers such as copper are also used, but result in reduced efficiency. The popularity of silver is due to the absence of the oxide layer formation, which imparts electrical insulating characteristics. Consequently, metallic fibers such as aluminum are rarely considered for this appHcation. 

The copper obtained from this process is about 99% pure, yet this is not pure enough for most uses, especially those involving electrical conductivity. To refine the copper further, it is made the anode of an electrolytic cell containing copper sulfate solution. With careful control of the voltage to regulate the half-reactions that can occur, the copper is transferred from the anode (where it is about 99 % Cu) to the cathode where it can be deposited as 99.999% Cu. At the anode there is oxidation of copper,... 

The combination of low optical absorbance and high electrical conductivity has attracted a lot of interest for transparent conductor applications. When coupled with its flexibility, it is widely seen as a possible replacement for indium-doped tin oxide (ITO), which has a sheet resistance of 100 Q/cm at 90 % transparency. By growing graphene on copper foils, sheet resistances of 125 Q/cm at 97.4% transparency have been achieved [19]. This has been improved by combining four layers with doping of the graphene, giving resistance of 30 Q/cm at 90% transparency, all done on 30-inch roll-to-roll production scale. 

A comprehensive report which focussed on the La2 xSrxCu O4-x/2+S ser es was published (139) in 1983 by this research group. In this broad review they reported the magnetic and electrical transport properties of these mixed-valent copper oxides in the temperature range 120-650 K. They concluded that the original semiconducting behavior in La2Cu04 transformed to semi-metallic behavior as the Cu3+ content increased with Sr-substitution. No experiments were conducted below 50 K, and therefore superconductivity was not observed. Three series of compounds, with 0.00 < x < 1.20 were... 

A determined search for superconductivity in metallic oxides was initiated in mid-summer of 1983 at the IBM, Zurich Research Laboratories in Riischliken, Switzerland. This research effort was an extension of previous work (145) on oxides, namely, Sr1.xCaxTiOs, which exhibited some unusual structural and ferro-electric transitions (see Section 2.2a). During the summer of 1983, the superconductivity research was focussed on copper-oxide compounds. Muller had projected the need for mixed Cu2+/Cu3+ valence states, Jahn-Teller interactions (associated with Cu2+ ions), and the presence of room temperature metallic conductivity to generate good superconductor candidates. These researchers then became aware of the publication by Michel, Er-Rakho, and Raveau (146) entitled ... 

The electrical conductivity was measured by W. H. Ross, who found that in all cases the conductivity of the salt soln. was increased with time, especially with the more dil. soln. This is due to the decomposition of the salts under the influence of the platinum-black of the electrodes with polished electrodes, the effect is considerably smaller. The base itself is oxidized even more rapidly than the salts. The soln. are in all cases decomposed by the platinum electrodes, and G. M. J. MacKay showed that tin does not decompose the soln. at all, while copper decomposes the soln. completely. The order in which the metals were found to decompose the soln. is tin, platinum, silver, nickel, mercury, and copper. The electrical conductivity of hydroxylamine, using tin electrodes, in terms of mercury at 18°, with v vols. of soln. per mol, is as follows ... 

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